Sports injuries are increasingly common, such as when tissues such as ligaments or tendons tear or detach from bone. Surgical techniques have been developed to reconstruct such soft tissues and to re-attach them to the relevant bone. One of the most common types of such injuries is the tearing of the anterior cruciate ligament (ACL) in the knee. The ACL connects the femur to the tibia at the center of the knee joint. Reconstruction of such tissues generally involves replacement with a graft, such as autologous or artificial tendon.
One method of graft fixation within the femoral tunnel involves the use of a fixation device on the anterolateral femoral cortex which is attached to the graft by means of sutures or tapes. The ligament anchor may be threaded through a femoral tunnel formed through the femur from the center of the knee. Sutures are attached directly to the fixation device on the outside of the femur above the knee the graft is looped through the suture before passing out of the femoral tunnel and being secured to the tibia.
One particularly important issue in the grafting operation is the formation of the suture loop attached to the fixation device, over which the graft is passed. Rigid suture loops require that the end surgeon have an inventory of multiple sizes of rigid loops depending on the size of the bone tunnel. Rigid loops also require an extra 3-5 mm of tunnel depth in order to maneuver the fixation device during the surgical procedure. Adjustable loops, on the other hand, require movement of the suture loop around the fixation device, causing abrasion to the attached graft. Concerns about adjustable loops inadvertently lengthening after graft fixation also exist.